Advances in the cultivation of leafy vegetables, such as spinach, lettuce, and various types of greens (e.g., collard, mustard, or turnip greens), have created a need for a comparatively inexpensive and portable harvester to harvest such vegetables. Many types of leafy vegetables have loose leaves and stems (as opposed to leafy vegetables that grow in “heads” of compacted leaves, such as certain types of lettuce). Current cultivation practices of loose leaf vegetables include planting the vegetables very densely, such that the leaves of each plant grow generally upward and are supported by the leaves of adjacent plants. While this increases the yield per acre of the vegetables, it also presents obstacles to harvesting the leaves. First, the leaves tend to bunch together near the combine teeth or cutting blade. As the mass of leaves near the teeth or blade increases, they begin to push other plants forward as the blade nears. This causes the blade to cut at a diagonal angle rather than substantially perpendicular to the leaf, thereby reducing the yield and resulting in unsightly partially-cut leaves, which are disfavored by consumers. This problem is even more acute in years of poor harvests, because the plants grow less densely and the leaves tend to spread outward rather than grow upward. Second, the leaves tend to bruise and damage easily. Furthermore, although industrial harvesters are available for large, industrialized farms harvesting thousands of acres, even the least expensive of these harvesters cost tens of thousands of dollars. The size and cost of these harvesters render them impracticable for use with smaller operations, such as family farms or farms that sell goods at farmers' markets or to groceries and restaurants specializing in locally grown foods.
Furthermore, even large industrial harvesters use a combine mechanism to motivate cut leaves onto a conveyor belt. Combine paddles are located forward of the cutting mechanism and motivate the leaves into the mechanism, but this can also result in the accumulation of leaves on the cutting mechanism.
What is needed, then, is a harvester for leafy vegetables that prevents leaves from bunching near the blade and does not bruise or damage the leaves.